John and Diane Foley were marking their son James' 40th birthday Friday with a prayer vigil. Photograph: Steven Senne/AP

The parents of an American journalist missing in Syria for nearly a year said Friday that recent events in that country have given them renewed hope of finding their son.

James Foley was last seen November 22 in northwestern Syria, where he was contributing videos from the civil war to Agence France-Presse for the media company GlobalPost.

His parents, John and Diane Foley, of Rochester, New Hampshire, were marking James' 40th birthday Friday with a prayer vigil. They've held frequent vigils to pray for his safe return.

In an interview with The Associated Press, they said the Syrian regime's decision to allow United Nations teams in to oversee destruction of chemical weapons could reveal more clues about their son's whereabouts and possibly lead to his release.

"We're very hopeful in that the UN teams that are going to Syria to find and destroy the chemical warfare weapons will basically be able to gather more information and perhaps even find Jim," John Foley said.

The Foleys also said they had a positive, second meeting Thursday with Syria's UN Ambassador Bashar Jaafari in New York.

"He was very empathetic, gave us his time as a parent would and that was very hopeful," Diane Foley said. "He has said the regime does not have him and feels likely he's being held in the north by one of the radical rebel groups."

Investigators have said they believe Foley is being held by the government near Damascus with one or more Western journalists, but the Foleys said they're less sure about that information now.

"With particularly the increased awareness that rebel groups are capturing people right and left, it's much less clear," she said.

New Hampshire's US senators, Kelly Ayotte and Jeanne Shaheen, released a joint statement pressing the State Department and FBI to continue to work for Foley's release.

"We remain hopeful that James will be found and safely brought home to his family," they said.

Foley was captured by Libyan forces in 2011. His captors then allowed him to make a phone call to confirm he was alive. The family has had no contact with him since his Thanksgiving Day abduction in Syria.

At least 100,000 Syrians have been killed in the country's civil war, now in its third year. The Foleys appealed to the world community to pray for an end to the conflict.

"We need peace. We need diplomacy," Diane Foley said. "There's so much suffering going on in Syria and we're acutely aware that our suffering is just a bit of it. We're just hoping at this time of prayer for Jim's birthday and peace in the Middle East, that there might be a softening of hearts."